Analysis On Seismic Performance Of A Large-span Science And Technology Museum With Steel Structure

Large-span structures are widely used in the public architecture due to its large space,various forms,beautiful appearance and good performance in recent years.As for the large-span science and technology museum with steel structure in this paper,is a irregular structure because of its irregular floor opening and the asymmetric structure.The earthquake will cause more damages in this kind of structures.Once it happens,it will cause great loss to people's life and property.Therefore,it is necessary to study the seismic performance of this structure.In this paper,the model of the large-span museum of science and technology was established by ANSYS and SAP2000,to analyzed the seismic performance of the structure in frequent and infrequent seismic actions.The main works of this paper are as follow:(1)The mode of vibration,natural vibration period,and dynamic characteristics were calculated by modal analysis and response spectrum analysis.By comparing the response spectrum analysis in different directions,it is concluded that the lateral stiffness of the structure in the x-direction is small,and the vertical earthquake has a critical impact on the large-span floor slab and cantilever part of the structure.(2)During time history analysis under frequent earthquakes,5 recorded seismic waves and 2 artificial waves were selected to compare and analyze the influence of seismic propagation from different angles on the maximum displacement value of the structure.The displacement value of some seismic waves at 165° and 255° was obviously greater than the principal axis direction,and the dynamic responses of the structure under 7 different seismic waves.The results of the same structure under different seismic waves vary greatly,but the general law is similar.The maximum Inter-Storey Drift Angle of the structure is under the limit value.The displacement increasement of the large-span part and the cantilever part under the X unidirectional and XZ combination earthquakes is compared.It can be concluded that the vertical earthquake has a significant impact on the two parts of the structure.(3)Three seismic waves were selected during time history analysis under rare earthquakes,X unidirectional and XZ combination earthquakes response of the structure were emphatically analyzed.Base shear conforms to our country's code.The maximum Inter-Storey Drift Angle of the structure is 1/116 under severe earthquake action,plastic hinge appeared mostly in floor 2,which has irregular floor opening,and most of them are still in the safety of life stage.Also there is a small amount of plastic hinge to get limit state.The performances of structure are in good condition,which satisfies the requirements of country's code.(4)Finally,the seismic performance of a large-span museum of science and technology in this paper is evaluated,and the results of this paper are summarized,and some suggestions are put forward for the design of this kind of structure in the future.